Universal grinding fixture



Sept. 28, 1954 A. L. MEYER 2,690,037

' UNIVERSAL GRINDING FIXTURE Filed March 21. 1950 s Sheets-Sheet 1 Zhwentor (Ittomeg Sept. 28, 1954 MEYER 2,690,037

UNIVERSAL GRINDING FIXTURE Filed March 21, 1950 3 Sheets-Sheet 2 Sept- 28, 1954 A. L. MEYER UNIVERSAL GRINDING FIXTURE 3 Sheets-Sheet 3 Filed March 21. 1950 $7004, F Z. Ms have Gttorneg Patented Sept. 28, 1954 UNITED STATES PATENT OFFICE UNIVERSAL GRINDING FIXTURE Adolf L. Meyer, Santa Clara County, Calif.

Application March 21, 1950, Serial No. 150,931

2 Claims.

The present invention relates to grinding fixtures and the like and is concerned more particularly with a device of the above character which is especially constructed for the sharpening of the cutting flutes or teeth of end mills, reamers, taps, and the like, as well as for other sharpening operations on tools, such as threading tools and Carboloy tool bits.

In general, it is the object of the present invention to provide a universal cutting tool holder by means of which any angle and clearance can be correctly and quickly obtained together with fast accurate indexing of the various flutes to grinding position. The fixture is also useful in various other types of machine operations as a work holder, for example, in producing eccentric pins, in drilling angular holes, in grinding annular end and side surfaces, and various other machining operations.

The above and other objects of the invention will be apparent from the following description of a preferred embodiment of the invention, as illustrated in the accompanying drawings, in which:

Figure 1 is a plan View of the fixture as it would be installed in place on the work plate of a surface grinder with the rinding wheel indicated at one side for a clear view of the fixture.

Figure 2 is a side elevational View of the fixture showing its relation to a surface grinder and with an end mill in position for sharpening.

Figure 3 is a vertical sectional View taken as indicated by the line 3-3 in Figure 2.

Figure 4 is a fragmentary longitudinal sectional view taken as indicated by the line 4-4 in Figure 1.

Figure 5 is an enlarged plan View of the work holding portion of the fixture showing the various angular graduations.

Figure 6 is a view illustrating the use of the tool in conjunction with sharpening of a thread cutting tool.

Figure 7 is a side elevational view of the adapter employed to hold a thread cutting tool.

Figure 8 is a view of the fixture in place in conjunction with a drill press illustrating the operation of drilling angular holes. V

Figure 9 is a diagrammatic view of a modification of the fixture employing a motor drive for turning the Work held therein.

Figure 10 is an elevational view of the fixture with a special base plate adapted for mounting on a lathe.

Figure 11 is a fragmentary side elevational view, partially in section, illustrating the mounting of the fixture on a lathe.

The usual method of sharpening tools having end cutting edges consisting of a plurality of flutes by the use of conventional equipment is a very laborious process and becomes so costly with small sized tools of this character that it is less expensive to buy a new end mill or tap rather than to regrind the cutting edges of a worn one. This is true because the grinding of each flute requires an individual setup operation of the fiute with respect to the grinding wheel. In accordance with the instant invention, the work holding fixture is designed for simple easy setup with sight alignment of the tool to be sharpened with respect to the fixture so that multi-fluted end cutting tools can be sharpened in a matter of seconds and with only a first initial setup required. The grinding can be done with the face of an ordinary surface grinding Wheel which can be of large diameter and therefore easier to dress and keep sharp and less subject to wear.

Referring to Figures 1 through, 5, the universal grinding fixture or cutting tool holder comprises a base member H] which is of generally rectangular contour andis provided with a flat bot tom surface H for positioning against the work table [2, for example, of a conventional surface grinder having a disc type grinding wheel 13. The base member In is provided with an elongated recessed slot [4 to receive a key I6 associated with a clamping bolt ll of the usual type employed in securing work on the work table I2. Adjacent one end the base member I0 is provided with an upstanding annular boss l8 which projects outwardly from the end of the base member l0 and is provided with an annular flange l9 about a central aperture 2 i. The plane of the face of the flange I9 is at exact right angles to the bottom surface ll of the base member.

The annular boss I8 is a mounting boss for a body member 26 having an apertured boss 2i journalled about the boss l8 and releasably secured thereto by means of a. cap screw 28. The tapered end of the boss 2'! is provided with opposite sets of graduations 24 extending in both directions from a central zero index which cooperates with an index mark 30 on the boss I8 of the base member.

The body member 26 is provided with a second annular boss 3| which has its axis at right angles to the axis of the boss 21. The bore of the boss 3| .(Figure 3) is enlarged at 32 adjacent one end surface 33 having four equally spaced graduations or index marks 34. The boss 3| provides a journalled mounting for a collet-holding quill 36 having a central tapered groove 31 for receiving the complementary end of a clamping cap screw 38 threaded into the boss 3|. The quill 36 is provided at its upper end with an annular flange 4| engaging within the recess 32 and forming a seat for an index collar 42 having a frusto-conicalouter surfaceaand: aslip liiz overlying-the edge of-the flange 4! and abutting the end surface 33. The quill 36 is shaped interiorly to receive a collet 66 of conventional construction having a keyed connectiontatr. 43

with the quill 36 and having associated therewith a suitable clamping nut iil and a;washer=492-. The frusto-conical surface. of the collar 42..

(Figure 5) is provided with a plurality of series of indexing graduations to permit the quick in:- dexing from flute to flute of any tool having from two to eight, tenor twelve flutesq-according to the numerals positionedradjacent therespective marks. Otherdesiredindex graduations may be provided. The zero index mark.at:51 has adjacent thereto a. clamping. setscrew/ 52. by means of which theindexingcollar Micah be connected securely to the quill 36-once the desired zero. setting of the-graduations:isdesired:

The operation of .the fixture in connection with thei=grinding..-of adouble flutedend mill Where centralclearance is desiredwbetween. the flutes willnow be described. The fixture is secured in place .on the work table !2 (as shown in Fig ures 1 and 2) and the tool or cutterto be shar pened is placed within the collet lfiand securely clamped therein. It will .be notedthatwith the. construction as shown herein; the. cutting tool being sharpened can be clamped as closely ad+ jacent. the cutting teeth as may. be desired so that no. warped or bent conditionzofd ts, shank will have any effect on the producingof' a true cutting 'edge on each of the flutesoffthe tool; With the cutter in place, the body memberzZB, is rotatedon the base member 16' setting the angular graduation 2 2 desired in alignment with the index mark 36- so'that the desired angle of grinding will obtain. Then the flu-te of the tool to be sharpened is lined'up by an indicator or by eye to the desired angular position with 'respect to the grinding wheel byrotating the sleeve 3.6..within itsboss 3|, and the cap screw 38 is. tightened toset the. tool securely in po'si tionasdesired. Thenthe. indexing... collar 421is adjusted until its zero graduation corresponds with aselected graduationBt-on the .body member 26.and1,the set screw 52:15 tightened tose t this zeropositioning into. the machine. The fiute aligned with the-grindingwheel. [351s "then: sharpened. Thereafter the cap screw-. 36: is loosened and, in this case, thequill 36 is turned 180 and is clamped at the 180 posi'tionby'theclamping" screw 38'. Then another pass of tool beneath the grinding wheel grinds the other cutting edge in exactly the same-manner in' which the'first' cutting edge was ground; Theoperaticn' with tools having different numbers, of'flutes will be the same except that .a selectedgroup ofindex marks on the. indexing collar 42 are usediin a-c-' cordance "with the number of flutes .of.the...cu'tting. tool. For the-grindingof center clearancaas shown in the doublefluted, endmillin Figures. 1 and=2, the procedure and.operationsiarerexe actly the same as described above-except that a different angular setting of the body member 26 on the base member [0 is selected.

For the sharpening of both Acme and U. S. standard thread cutting tools, a bit adapter 56, as illustrated in Figures 6 and '7, is used. The adapter 56 has a cylindrical extension 51 for positioning in a collet 46 having the proper diameter opening to receive it. The body of the adapter 56 is provided with an angularly positioned transverse groove 58', .for example, at an angle of 29 as employed in some thread cutting-tools, with a plurality of set screws 59 provided in a wall thereof to engage the thread cutting tool 6|. Theada-pterz-56 is also provided with a second bit receiving groove 56a which extends in the same general direction as the first groove 58 and is exactlyatright angles to the axis of the shaft extension 51. The second groove 56a is also provided with set screws 5!! in a wall thereof. With the thread cutting tool in the second groove 58a, its top surf-acevcan berea-dily ground. InF-igure 6;; ,theadapter 56 is-shownin dotted lines at an angular setting for grin'dingthe desired clearance on aside faceof the thread cuttingtool.

It will be appreciated that other work-holding fixtureslcan be employed in the collet in accordancewith the character andshape of the tool to be held in grindingposition.

Figure 8-.illustratesuse'o'f the fixture for angle drilling Of'hOlES. mountedto-nz'thework table 66; of .adrill press having: a tool-carryinghead 61 and the conventional type of adjusting. means 68.. An adapter 69, similar to the adapter-56 but having a single wide groove similar to the groove tdtherein, is mounted in the fixtureand the work piece H is secured therein. Inorder'to guide the drill I2, thebody member. 261s provided witha pad 13 having a key-way 14 therein. (Figure 1) for alignedmounting of abracket l61'by means of a clamping cap screw H. The bracket 16 has at its upperen'd a drillbushing 16 positioned with reference to. the workltoguiderthe drill 12 in entering at the proper angle. The adapter 69, shown in Figure-8, is .used also to hold the rectangular shanks... of: Carboloy tool bits. during sharpening;

In Figure 9, amodifiedform of the Work-holder or, fixture .isprovi-dedinwhich the work can be turnedvduringa operationhthereon, and, for this purpose; the body member 2611- is provided with an aperturedzbossiil on oneend of which an electric motor 82 is mounted. J ournalled in the boss 61. in any. suitable fashion is; aworm 83 carried;at theend. of the'shaftofthe motor 82 and engaging a worm gear 86 carried by; the collet holding-quill 3600. With this type of fixture, the powerdriven quill 36a can be rotatedduring the grinding of an annular surface on a work piece held in the collet of the fixture.

FigureslO" and 11 illustrate a modified form of the invention in which the base plate lflais inthe form of a disc having a transverse-key=way 91 across its rear" face and adapted for mounting withina recessed'work plate 92 carried by'the shaft-93 of a lathe. The base plate Hm carries an'upstanding bracket 95 provided with alaterally projectingannular boss 21a-on which the body mem ber. 2610f the fixture is. journalledin the manner: described. in. connectionwith the forms of the inventionshown in Figures 1.to 5. One or morekeys Ei l'on the face plate 93a engage the ekeyway 91 and a=p1uralityof micrometer adjusting screws 96 in the annular flange 91 of the, adapter plate .62. enable accurate off-center In this. instance, the fixture is positioning of the axis of the collet of the fixture with respect to the axis of the lathe for the machining or grinding of eccentric surfaces or pins on a work piece. The upper and lower screws 96 have tapered ends to engage transverse grooves 98 and wedge the parts .together.

With reference to Figure 3, it is to be noted that the collet-holding quill 36 is adapted to be removed from the boss 3| with a work piece clamped in the collet 36 without disturbing the relation of the work piece to [the indexing collar 42. This is accomplished by turning the cap screw '38 until its point recedes from the groove 31, at which time the quill 36 can be withdrawn from the collar 3|, the clamping nut 48 and the washer 49 being of smaller diameter than the internal diameter of the boss 3| to permit this withdrawal without disturbing the clamping of the work piece. This enables use of thework piece in connection, for example, with a drill press, or permits insertion of a second quill 36 with another work piece without disturbing the adjusted relation of the work piece in the first quill 36 to the indexing collar 42.

While I have shown and described preferred embodiments of the invention, it will be understood that the invention is capable of variation and modification from the forms shown so that its scope should be limited only by the scope of the claims appended hereto.

I claim:

1. A universal fixture for grinding and the like operations comprising an elongated base member having a surface for engagement with a support, said base member having an annular boss at one end thereof projecting beyond said surface and having its axis positioned in parallel relation to said surface, an index mark on said boss, a body member having a pair of apertured bosses with their axes positioned at right angles to each other, one of said apertured bosses being journalled about said annular boss of said base member and having angle 'graduations for cooperation with said index mark, said body member being positioned in outboard relation to said base member, means for releasably securing said body member with respect to said base member, a collet-holding quill journalled in the other of said bosses of said body member, said quill having an annular groove intermediate its ends, a clamping screw threaded in the other of said bosses and engaging said annular groove, a collet in said quill, annular clamping means axially aligned with said collet for securing said collet in said quill and for securing a work-piece in'said collet, said clamping means having a diameter less than the inner diameter of said other of said bosses whereby when said clamping screw is withdrawn from engagement with said annular groove, said quill and said collet are freely withdrawable from said other of said bosses, a second index mark on said other boss, an indexing collar journalled about said quill and having graduations for cooperation with said second index mark, and means for releasably securing said collar to said quill.

2. A universal fixture for grinding and the like operations comprising an elongated base member having a surface for engagement with a support, said base member having an annular boss at one end thereof projecting beyond said surface and having its axis positioned in parallel relation to said surface, an index mark on said boss, a body member having a pair of apertured bosses with their axes positioned at right angles to each other, one of said apertured bosses being journalled about said annular boss of said base member and having angle graduations for cooperation with said index mark, said body member being positioned in outboard relation to said base member, means for releasably securing said body member with respect to said base member, a collet-holding quill journalled in the other of said bosses of said body member, means for releasably securing said quill in the other of said bosses, said securing means being disengageable from said quill, a collet in said quill, and annular securing means axially aligned with said collet for attaching said collet tosaid q-uil-l and for securing a workpiece in said collet, said securing means being disposed within the internal diameter of said other of said bosses to permit bodily removal of said quill, said collet and the workpiece held thereby, a second index mark on said other boss, an indexing collar jo-urnalled about said quill and having graduations for cooperation with said second index mark, and means for releasably securing said collar to said quill.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 665,303 Bath Jan. 1, 1901 1,352,703 Tulek Sept. 14, 1920 1,385,519 Calhoun July 26, 1921 1,703,017 Singer Feb. 19, 1929 1,908,155 J-orgensen May 9, 1933 1,981,174 Hille -1 Nov. 20, 1934 2,324,608 Walling July 20, 1943 2,325,364; Boenin-g July 27, 1943 2,379,520 Hartung July 3, 1945 2,432,058 Wiken et al Dec. 2, 1947 2,595,950 Keebler May 6, 1952 FOREIGN PATENTS Number Country Date 541,433 Great Britain Nov. 26, 1941 

